Originals are Höller marked only. Blade length is longer than the 20 cm or 25 cm we often see. PD Lüneschloss etched fakes have been around for decades. The blade’s etch is far less detailed than originals. Poorly fitted grip plates. There are more tells that I’ll keep quiet about.
I agree with Billy. I will also point out that some of these fake etched blades were made up on original KS98. These will generally show a difference between the etched maker logo and the etch on the blade so that is something else to look for.
Fakes of this model have been around many years but can be easily discerner from period originals with not too much effort. Typically the rivets are poorly done or the grip emblem is the incorrect style for the period.
Also, the etched on original Hundertschaft presentation bayonets are very well executed whereas nearly all reproductions are poorly done, as with this example. There are other minute details but you get the idea. A collector need not have studied these pieces to identify a fake. Remember that starting out a skeptic will save you a headache down the line.